FAQ: CoolSpools and Overlay alignment

If you need help with any of the techniques described below, feel free to contact our support team.

My overlay doesn’t line up properly

Specifying the printer device

Overlay alignment is a complex area, and how an overlay lines up on the page can sometimes be dependent on factors that CoolSpools can’t know about without additional information, such as what kind of printer you’re using and how its margins are set etc.

By default, CoolSpools emulates a true IPDS printer, but if you’ve developed your application for a Host Print Transform printer, the chances are your printer will align overlays a little differently. See this IBM document for details of how Host Print Transform (HPT) behaves different from true IPDS printers.

The solution is to tell CoolSpools that the spooled file was developed for printing on a Host Print Transform (HPT) printer. CoolSpools will then implement a slightly different set of rules for overlay positioning. You do that by naming your HPT printer on the PRTDEV parameter of the CVTSPLPDF command etc., for example:

CVTSPLPDF ... PRTDEV(MY_HPT_PRT)...

This will also allow CoolSpools to examine the printer device description and derive certain attributes from the model type of the printer.

Another option is to use:

CVTSPLPDF ... PRTDEV(*HPT)...

In this case CoolSpools will emulate a generic Host Print Transform devoce.

Adjusting margins

If your printer has its margins set differently from the norm, CoolSpools can’t know about that. You may need to adjust the page margins slightly using the MARGINS parameter to get your overlay to line up.